Dear Dr Gormley-Gallagher,

Thank you for your responses to the referee comments and my own editorial comments. I invite you to submit your revised paper so we can return it to the referees.

Best regards

Richard

Dear Dr Gormley-Gallagher

Thank you for submitting your revised manuscript, accompanied by clear and comprehensive responses to the review comments. I sincerely apologize for the long delay in providing you with a response.

I am pleased to confirm that we can accept your paper for publication in Earth System Dynamics, subject to the following minor revision.

Referee 2 suggests that you give more prominence to issue of coarse resolution in GCMs as a potential limitation on using these tools to study land surface influences is the spatial resolution, and that you consider including a recommendation that this could be a further avenue for research and model improvement. I note that you point out the limitations of coarse resolution in the text of the paper, and it may be that using higher resolution may well be part of what you have in mind in your remark in the abstract "highlight the need to carefully represent and evaluate land management in climate models" - if so, please be more explicit about this in the abstract. Similarly, I think it would be worth briefly highlighting the issue of spatial resolution in the conclusions, and considering whether you wish to include a specific recommendation on this point.

For reference, I include Referee 2's remarks on this point below.

Richard

Further remarks from Referee 2:

"The authors took time to respond. Thank you.

My remaining comment is that they still make this, in my view, poor assumption:

“ An underlying premise of this paper is that GCMs remain the primary tool for providing long-term projected changes in the climate system and have been often used for studying land cover and land management effects on climate”.

Unfortunately, landscape heterogeneity, including resulting mesoscale circulation features, on spatial scales that their model cannot resolve are very important. Indeed, unless the models can resolve mesoscale features such as sea breezes, (which is an analog for landscape forced mesoscale circulations) they are going miss significant effects. Here is one example illustrating why higher spatial resolution is essential:
Marshall, C.H. Jr., R.A. Pielke Sr., L.T. Steyaert, and D.A. Willard, 2004: The impact of anthropogenic land-cover change on the Florida peninsula sea breezes and warm season sensible weather. Mon. Wea. Rev., 132, 28-52.
A second paper, dealing with dispersion over variations in land surface forcing also shows the importance of smaller scale resolution.
Pielke, R.A. and M. Uliasz, 1993: Influence of landscape variability on atmospheric dispersion. J. Air Waste Mgt., 43, 989-994.
Even on regional scales, they will miss effects due to lack of spatial structure.

Their model can only resolve features that are at least 4 horizontal grid increments in each x-y direction. The model set up has

"The period 1976-2010 was simulated with a horizontal pixel resolution of 0.9° latitude × 1.25° longitude."

This means they can only resolve, with any fidelity, features 3.6 degrees by 5 degrees; much too coarse to resolve important landscape effects on the local, mesoscale and regional scale.

Here is an example of an analysis for aerosols and found a large potential influence on regional circulation features;

Matsui, T., and R.A. Pielke Sr., 2006: Measurement-based estimation of the spatial gradient of aerosol radiative forcing. Geophys. Res. Letts., 33, L11813, doi:10.1029/2006GL025974.

A similar large effect is expected with landscape management and landscape changes.

I recommend more text be added on this issue. One suggestion for future work is to run higher spatial resolution (both regional; mesoscale) model runs for selected shorter time slices, and compare results to the coarser resolution results they have with the global models.
After the authors and Editor consider this recommendation, I recommend acceptance."

Dear Dr Gormley-Gallagher,

Thank you for your revised manuscript, responding to the additional review comment. I am happy to accept the paper in its current form. It is a valuable contribution to the literature - thank you for submitting to Earth System Dynamics.

Best regards

Richard